Aeroplane-sighting device.



F. L. SLACK.

AEROPLANE SIGHTING DEVICE. APPLIGATION FILED IEB.7, 1911.

1,028,502,, Patented. June 4, 1912.

2 SHEETS-SHEET 1.

/' HH HIII WITNESSES: INVENTOR F. L. SLACK.

AEROPLANE SIGHTING DEVICE.

APPLICATION FILED PEB.7, 1911.

1,O28 5O2, Patented June 4, 1912.

2 SHEETSSHEET 2.

WITNESSES: I/VVEIVTOR g 2 FFQWK L.J/0ck 6 flai 35 FRANK L. SLACK, 0F IireLEwoon, oanrronnra.

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,velocity of the projectile at the instant it released. By means of my range finder a, View of the approximate theoretical land ing point is projected on ground glass or mirrorwithin easy access of the operator of the machine. This beneficial result I accomplish by'means ofthe, device herein described and shown in the-accompanying drawings, in whichthroughout the drawings.

Figure 1 is a topplan view of my'range' finder attached, to a section .of the frame-of an aeroplane; Fig. 2 is a side elevation of the same-parts shown in Fig. 1; Fig; 3 is a longitudinal section of the camera or view box taken on the dotted line aa in Fig. 1 and Fig. 4; is a transverse cross sectional view taken on the dotted line 6-2 in Fig. 2.

Like characters refer, to like Referring to the details of construction: 1 is a bar connected with a movable shaft 2; 3 and 4 are cups or wind 'vanes attachQto the ends of the .cross bar 1; 5 is -a section of the framework of ahae'roplane; 6 is a-bearing provided in the frame to allow the shaft to rotate freely; 7 is a frame'provided to guide the shaft 2 and a circularopening through this guide frame serves for-a second bearing for the shaft 2; 8 and 9 are collars above and below the serve to prevent longitudinal movement inthe shafting 2.

' 'and 12 weights of anordinary typeof cen- 10 and 13 are collars; 11. connectingbars,

trifugal governor, connected at one nd-with. the shaft 2 and at the other end with a shaft 14 16- and 17 referto sections of the supporting framework through suitable openings in'whiclithe shaft '14 o crates; 18

is a *collanon' the'extreme end o the shaft 14; 19 is a spiral spring operating between the collar 18 and the frame 17. A pin 20 specificationpf le tterslatent; Application filed Februaiy 7, 1911. Serial No. 607,033.-

parts guide frame 7. These the collar 18 engages a slot 22 in the end of PatentedJune4,1912. I

the lever 21. The lever 21 operates on the pivot 25 as a fulcrum; 23 is a camera or view box attached to the lever 21; 243is a telescope which projects the image within its 'field upon the mirror 25 and thence it is refiected upon the screen or ground glass 26;

27 is an eye-piece through which the operator views theimage cast upon the screen 26.

If desired the ground vided with .avert-ical line 9 and cross lines 30 marked or out upon its surface for the purposes hereinafter explained. a

From an' aeroplane stationary in the air a rectly, beneath the aeroplane, but if the aeroa plane is-in motion the. momentum of the prolass may be projectile'would cause it to fall at. some point in advance of apoint directly: under the aeroplane at the inst-antpf release. Therefore, in operation it is assumed that "the greater the velocity of the aeroplane the I greater will be the distance traversed by the projectile beforeit reaches the target from an given height. a

To. be effective as a range. finder under ideal atmospheric, conditions the angle of line of sight with reference to the aeroplane should be varied from vertical in a station- .ary' position to the angle adapted to the various speeds.

pally three separate elements operating to- 'gether-to produce the desired result. These parts in the vform of construction shown In operatlon-mydevice comprises-princifindercompri'sing the parts 23,24, 25, 26 V and 27.

'lnoperatipn the wind causes the vanes or cups to revolve-and motion is thus transmitted to the shaft 2. As the speed of the machine increases the speed of the shaft increases in direct proportion. The governor onthe' end of the'shaft 2 also revolves and as its speed increases the centrifugal force causes the weights to separate and through the connecting links 11 a longitudinal force is transmitted to the shafts 2'and 14.. The shaft 14 is drawn in toward the governor and the spring 19 is compressed.

Through the lever 21 the camera box and vtelescope is. inclined so that line projectile released would fall to a point di-: D

40 ing the surface of the earth beneath the aeroplane and suitable automatic device for of sight is advanced as the shaft 14: is drawn in toward the governor. By means of the tension of the spring 19 or by a suitable compound system of levers the amount of movement may be varied according to the degree of inclination found to be required for the various speeds.

The camera or view finder is so arranged that an image of the field covered by the lens is projected upon the glass and a vertical line upon the glass indicates the center of the field of vision. The element of altitude I also enters into probable range of the projectile and to provide for this the horizontal lines 80 are provided on the screen, inscribed with various altitudes. These lines out the reflected image into several zones which are covered by the same speed at'the various altitudes. The operator being aware of his altitude by means of abarometer oraeronoid may immediately choose the particular zone corresponding to his altitude and by means of the vertical line the point inthis zone under his range at any given point.

The means of measuring the speed of the aeroplane or dirigible balloon may consist of 'a wind gage apparatus similar to the one shifting the field of vision of the observing apparatus as the speed of the aeroplane is increased or decreased.

2. In an aeroplane sighting device: the combination of a suitable observing instrument for viewing the surface of the earth from an aeroplane; a suitable governor; suitable means for transmitting motion from'the governor to the observing instruments and suitable means for increasing and decreasing the speed of the governor as the speed of the aeroplane increases or decreases, all substantially as set forth.

3. In an aeroplane sighting device: the

combination of a suitable observing apparatus; a suitable governor; means for transmittlng motion from the governor to the tially as described.

observing apparatus; a driving apparatus propelled by air currents; and means for transmitting powerfrom the driving apparatus to the governor.

4. In an aeroplane sighting device: an air propelled apparatus fortransmitting motion to a shaft; a suitable governor attached to said shaft; a governor shaft; a suitable ob- 7 serving apparatus; a suitable lever for transmitting-motion from the governor shaft to the observing apparatus and thereby varying the position of the observing apparatus.

'5. In an aeroplane sighting device: the

combination of a suitable air propelled appa-. ratus; suitable means for transmitting mo tioii from the air propelled apparatus to a governor; a suitable governor operated by the air propelled apparatus; suitable apparatus for connecting the said governor with strument arranged to be shifted by means of said governor and connecting ap'p'aratusand a sultable framework attached to an aeroplane for securing the said parts in their relative positions, alLsubstantially as described and for the uses and purposes set forth. i I

6'. In an aeroplane sighting device: vanes 3 and 4 attached'to a revolving arm 1; said arm 1 attached to a vertical shaft 2; collars 8 and 9 for preventing longitudinal motion an observing instrument; an observing in-j of the shaft 2; a collar 10, connecting links 11, weights 12 and collar 13 constituting a governor attached to theshaft 2 and to the shaft 14; a shaft 1 1. whichis supported by the governor and which rotates with the governor; a spring 19 for regulating the vertical motion of the shaft 1i; acollar 18 and pin 20011 the lower end of the shaft 14; a lever 21 slotted at one end to receive the pin 20; a pivot secured tothe framework upon which said lever 21 operates; a suitable framework attached to the aeroplane frame 5 and constructed in such a manner as to retain all the parts in their. relative positions; a suitable view box 23 attached to said lever 21; a telescope attached to said box 23 and adapted to throw anv image of the field covered by it upon a reflector 25 in said box, a reflector 25 by means of which the image is thrown upon a screen 26; said screen 26 placed in said box 23 and an eye piece 27- through which sa d screen may be .seen by the operator, all substan- FRANK L. sLAoK. Witnesses AND EW K. MAn'rELL, HANNA MENDENHALL. 

